There's quite a few of his other books on there too. They all have the original NEL covers with the NEL logo airbrushed out, there's no copyright/publisher information, and there has been no news anywhere that these were going to be re-released in any form.

Skinhead Times were the last publisher (mid-90s), they have been releasing some of their non-fiction titles on Kindle but said a while ago that James Moffatt had no surviving family so they wouldn't be able to re-release his Richard Allen books.

These days how can you tell? I mean you can get a copy of a PD book, Moby Dick, for example from Gutenberg and with Sigil and Calibre you can create a working TOC (or fix one if some work needs doing on it) and then search the web for a good cover for it. And of course a book isn't always PD when it's found on the web. There was the problem with Orwell's book of "1984" a while back as well.

BTW, if the Richard Allen books were going to be re-released in any form it would have been big news among the circles I'm part of. They definitely wouldn't be able to use the original 1970s covers because Skinhead Times couldn't get clearance for them for their reprints.